Earthshatter and Rageforged Mechanics

I have a two-part question about the interaction between the Rageforged support gem and Rage.

Part 1: Rageforged and Rage scaling Rage grants 1% more damage per point of Rage. If you have 100 Rage, you are effectively dealing 100% more damage. The Rageforged support gem causes supported skills to consume 10 Rage on use in order to gain 35% more damage. In this situation, when you use a skill at 100 Rage with Rageforged linked, is the damage calculation treated as if you are at: 90 Rage (after the 10 Rage is consumed), plus the Rageforged bonus, or 100 Rage for the Rage bonus, plus the additional 35% Rageforged bonus.

Part 2: Earthshatter, secondary damage, and Rage snapshotting Earthshatter deals damage in 2 stages: the initial Slam, and the Explosion triggered later by a Warcry. Assume you have 100 Rage and Rageforged is linked to Earthshatter. When you use Earthshatter, 10 Rage is consumed due to Rageforged, leaving you at 90 Rage. When you later trigger the spikes with a Warcry, does the Explosion damage scale off: the original 100 Rage at the time of the Slam, or the remaining 90 Rage at the time the Explosion occurs?